DIGESTION AND ABSORPTION
ilorgagni is large, and the levatores and tensores palat: are more horizontal owing to the prognathisra of the skull than In Man.
The tesophayus is entirely behind the trachea in ihe neck. It has similar relations in the neck arn.1 thorax to those in Man. The mucous :iieniLrane is thrown into prominent longitudinal folds in the
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FIG. 40.The tongue of the Bornean Gibbon showing the uppe; and lower surfaces and a highly magnified lateral organ* a., central fungifonn papilla ; 6., tonsil; c., epiglottis ; d., conical papilla; ?., papillary border ; in., frenum ; 71., frenal lamella; o., non-pigmented area; p., median sulcus ; r., pigmented area. The thick, black dot above the lateral organ in the lowest figure is the most lateral vallate papilla.
cervical and thoracic parts, but the former are more numerous and closer together. The walls are thinner and more dilated in the lower part of the oesophagus. In the upper part the inferior constrictor joins the outer longitudinal muscular coat of the oesophagus,, which increases in thickness from above downwards, and becomes continuous with the outer coat of the gastric musculature. The circular muscle coat thickens from